ELECTROMAGNETIC SPECTRUM All waves travel the SAME speed (the speed of light) 300,000 km/sec (186,000 miles/sec) in a vacuum 10 4 Hz 10 6 Hz 10 8 Hz 10 12 Hz 10 14 Hz 10 16 Hz 10 18 Hz 1 million 1 trillion 1 million trillion Low Frequency Long Wavelength Low Energy High Frequency Short Wavelength High Energy It takes 8 minutes for light waves from the sun to reach the earth. Images and information taken from this web site: http://imagers.gsfc.nasa.gov/ems/waves3.html
RADIO WAVES The wavelength is from 3 km to 30 cm. The frequency range is from 10 4 Hz to 10 8 Hz 10,000 to 100,000,000 Longest wavelengths Can be longer than a mile or as short as a foot.
Uses of Radio Waves Bring music to your radio Cellular phones These waves are much smaller that TV and FM radio waves. Wireless router for computer Demo flashlight transmitting signal
How a radio station works http://phet.colorado.edu/en/simulati on/radio-waves
Wireless game systems Dish Remotes UHF signals Antenna to receive remote signals attached to box. Satellite TV signals
Study Space.
Radio telescopes
MICROWAVES Wavelength is from 300 cm to.3 cm Frequency range is from 10 8 Hz to 10 10 Hz Wavelengths measured in centimeters!
Uses of Microwaves Heat our food in a microwave oven.
Microwaves are good for transmitting information like telephone calls and computer data from one city to another.
Shorter microwaves are used in remote sensing. These microwaves are used for radar like the Doppler radar used in weather forecasts.
RADAR is an acronym for "radio detection and ranging". Radar was developed to detect objects and determine their range (or position) by transmitting short bursts of microwaves.
VIEWS OF EARTH FROM SPACE Viewing the Earth from space. Microwaves can penetrate haze, light rain and snow, clouds and smoke, (C-band). This image shows sea ice breaking off the shores of Alaska.
(L-band). Image of the Amazon River in Brazil. L-Band radar image of some mountains on the edge of Salt Lake City, Utah.
INFRARED LIGHT The wavelength is from 300 micrometers to 3 micrometers The frequency range is from 10 11 Hz to 10 14 Hz Far infrared" is closer to the microwave region Size of a pin head "Near infrared" light is closest in wavelength to visible light Size of cells (microscopic)
Far infrared waves are thermal (heat) Sunlight, a fire, a radiator or a warm sidewalk is infrared.
Heat Lamps over food
Night Vision Goggles
Rattlesnakes, have sensory "pits", which are used to image infrared light? This allows the snake to detect warm blooded animals, even in dark burrows!
Remote controls use short infrared waves that are not hot (That are not radio remotes) Must be in direct line.
Pictures of earth from space show more details This is great for studying cloud structure. Darker clouds are warmer Lighter clouds are cooler.
Film captures images of light that is reflected Normal light Taken with infrared film Chlorophyll in plants reflect near infrared waves
Study the solar system The hazy, horizontal S-shaped feature that crosses the image is faint heat emitted by dust in the plane of the Solar System.
VISIBLE LIGHT Red: 0.7 micrometers to Violet: about 0.4 micrometers. 430 trillion Hz, seen as red, to 750 trillion Hz, seen as violet. ( 7.5 x 10 14 ) Smallest bandwidth section of the EM spectrum
White light shines through a prism or through water is broken apart into the colors of the visible light spectrum.
The color of an object that we see is the color of light reflected. All other colors are absorbed.
Visible light is the only part of the electromagnetic spectrum that our eyes can see. Our whole world is oriented around it. Use instruments to such as: Cameras, Telescopes, Microscopes.
Lasers
ULTRAVIOLET LIGHT The wavelength is from.3 micrometers to 3 nanometers (billionth) The frequency range is from 7.5 x 10 14 Hz to 10 16 Hz
Ultraviolet (UV) are invisible to the human eye, Some insects, like bumblebees, can see them!
UV light causes sunburns (and tans) Ozone layer of atmosphere blocks UV rays. UV index developed to help protect people.
Purify Water
Image of sun capturing only Extreme Ultraviolet wavelengths
Study stars and galaxies by studying the UV light Picture of Earth taken from a lunar observatory! This false-color picture shows how the Earth glows in ultraviolet (UV) light.
The ultraviolet light (top row) shows new stars that many times more massive than the sun, which glow strongly in ultraviolet light. Visible light (bottom three images) This shows mainly the older stars which glow in the red and yellow range. Taken by NASA's Ultraviolet Imaging Telescope (UIT) on the Astro-2 mission.
X-RAYS The wavelength is from 3 nanometers (billionth) to.03 nm The frequency range is from 10 16 Hz to 10 17 Hz (thousand trillion) We usually talk about X-rays in terms of their energy rather than wavelength. This is partially because X-rays have very small wavelengths.
Discover by accident in 1895 by Wilhelm Conrad Roentgen, a German Scientist. Roentgen called it "X" to indicate it was an unknown type of radiation. X-ray of hand With ring on finger
When X-ray light shines on us, it goes through our skin, but allows shadows of our bones to be projected onto and captured by film. Medical uses such as: X-rays of teeth and bones
Airport security Check for flaws in welding
Many things in space emit X-rays, among them are black holes, neutron stars, binary star systems, supernova remnants, stars, the Sun, and even some comets! Comet x-ray image Sun x-ray image Study the solar system
X-ray image only This image is special - it shows a supernova remnant - the remnant of a star that exploded in a nearby galaxy known as the Small Magellanic Cloud. The false-colors show what this supernova remnant looks like in X-rays (in blue), visible light (green) and radio (red).
GAMMA RAYS The wavelength is from.03 nanometers to.003 nm The frequency range is from 10 18 Hz (one million trillion) Gamma-rays have the smallest wavelengths and the most energy of any other wave in the electromagnetic spectrum.
Kill cancerous cells. Gamma Knife surgery: Rays combine to kill tumor
Sterilize materials that can t be exposed to high heat. Kill bacteria and insects in packaged food.
Study solar system Things like supernova explosions neutron stars, pulsars, and black holes are all sources of celestial gamma-rays.